1. Field of the Invention
The present invention relates to a fluid mixing apparatus and a fluid mixing system for mixing two or more inflow fluids or causing reaction between them.
2. Description of the Related Art
Recently, a chemical reaction in which materials are diffused in a short period of time in micro-channels has attracted attention as an innovative technology for making reacting and mixing more efficient and faster, and a precise reacting and mixing system (micro-reactor) for chemical solutions and the like using micro-channels formed by a micro-manufacturing such as etching has been proposed.
For example, in International Patent Application No. WO 00/62914, as shown in FIGS. 53 and 54, a micro-reactor 600 for mixing two kinds of solutions is disclosed. Comb-shaped micro-channels 604 of 20 μm in width are provided so as to alternately mesh with each other, and alternately arranged fluid 1 and fluid 2 flow as a laminar flow. A discharge opening 608 has a slit shape of 60 μm in width, and disposed along a direction orthogonal to the comb-shaped micro-channels. The fluid 1 and the fluid 2 are formed in alternately arranged bands in the discharge opening and discharged.
However, in the publication No. WO 00/62914, because the kinds of fluids that can flow are limited to two, in order to allow three or more fluids to flow for mixing or reaction, plural apparatuses are required, and accordingly, these lead the following problems: (1) the structure of the apparatus becomes complex and large-scaled, and equipment cost and maintenance cost for cleaning and others become higher; (2) a large number of fluids cannot be mixed simultaneously, and the design of the reaction system becomes largely restricted (that is, three or more fluids cannot be simultaneously mixed and caused to chemically react with each other); (3) its manufacturing process is based on the silicon process used for semiconductor manufacturing, and thus, usable materials are limited and performance such as strength and chemical resistance deteriorates.
Further, the micro-reactor 600 can also be applied to reactive fluids, and a reaction product S can be efficiently obtained by causing the fluid 1 and the fluid 2 to react with each other, however, because the reaction product produced in the vicinity of inner walls of the slit adheres to the inner walls, there is a problem that the fluids cannot flow smoothly, and further, there is fear that the channels might become occluded. As measures against that, mirror polishing the inner walls of the slit and the like has been considered, however, because the channels are miniaturized, the measures have not put into practical use yet.
In addition, in U.S. Pat. No. 5,534,328, as shown in FIG. 55, a micro-reactor 610 comprised by laminating plates on which micro-channels are formed is disclosed. The micro-channels are processed on the plates having good manufacturing aptitude, and a three-dimensional micro-reactor having a complex construction is manufactured by laminating the plates.
However, gaps produced in bonded surfaces between adjacent plates and bumps of through holes cannot be eliminated. Accordingly, there has been a problem that the gaps and bumps cause a turbulent flow. Further, because the reaction product easily adheres to the gaps and steps, there has been another problem in that channels might be occluded.
In order to solve these problems, in Japanese Patent Application (JP-A) No. 2002-292274, as shown in FIGS. 56A through 56C, a micro-reactor 620 provided with introduction channels combined into a main channel has been proposed. In this micro-reactor 620, the fluid 2 is prevented from contacting with the main channel walls by allowing the fluid 2 to flow from the introduction channel 624 into the fluid 1 flowing through the main channel 622, thus, the occlusion of the micro-channels caused by adherence of the reaction product to the channel walls is reduced.
However, in JP-A No. 2002-292274, because the micro-reactor 620 is formed by allowing the main channel to penetrate the introduction channels, the manufacturing aptitude is not very good compared to the micro-reactor 610 in U.S. Pat. No. 5,534,328 using LIGA process and the like. Thus, in the case of mass production of the micro-reactor 620, it is assumed that there will be difficulties with regard to production time and production cost. The LIGA process is a manufacturing method for mass-producing components by molding after manufacturing a mold with nickel or the like (electro-molding) with a master formed by a semiconductor manufacturing method such as lithography and precision etching as an original form.
Because it is important for the micro-reactor that micro-channels be formed within the micro-space, increasing in yield by essentially the enlargement of the apparatus cannot be expected. Furthermore, the yield obtained from each micro-reactors is a minute amount. Accordingly, increasing in the number of apparatuses becomes important for increasing the yield. Thus, a micro-reactor is required to have good manufacturing aptitude, that is, it can be mass-produced at low cost in a short period of time.
In addition, in the publications of U.S. Pat. No. 5,534,328 and JP-A No. 2002-292274, because the micro-reactor cannot be easily disassembled into component members, there have been difficulties in that maintenance of the apparatus and replacement of-components are not easy.
As described above, a micro-reactor that satisfies all of the followings (1) to (4) has not been realized. That is, (1) channels are prevented from being occluded with the reaction product by covering the channel wall with a fluid; (2) manufacturing appliance is good and desired yield can be obtained by increasing the number of apparatuses; (3) three or more fluids are efficiently mixed or caused to react with each other; and (4) maintenance and the like can be easily performed.